Update Horizontal Pod Autoscaler to v2

Update to autoscaling/v2, as autoscaling/v2beta2 is deprecated since kubernetes v1.23.

webserver/templates/hpa.yaml

 {{- if .Values.autoscaling.enabled }}
-apiVersion: autoscaling/v2beta1
+apiVersion: autoscaling/v2
 kind: HorizontalPodAutoscaler
 metadata:
   name: {{ include "webserver.fullname" . }}
@@ -17,12 +17,16 @@ spec:
     - type: Resource
       resource:
         name: cpu
-        targetAverageUtilization: {{ .Values.autoscaling.targetCPUUtilizationPercentage }}
+        target:
+          type: Utilization
+          averageUtilization: {{ .Values.autoscaling.targetCPUUtilizationPercentage }}
     {{- end }}
     {{- if .Values.autoscaling.targetMemoryUtilizationPercentage }}
     - type: Resource
       resource:
         name: memory
-        targetAverageUtilization: {{ .Values.autoscaling.targetMemoryUtilizationPercentage }}
+        target:
+          type: Utilization
+          averageUtilization: {{ .Values.autoscaling.targetMemoryUtilizationPercentage }}
     {{- end }}
 {{- end }}